The invention relates to railroad cars, especially the trucks or bogies which are located at opposing ends of a railroad car to support the car on the rails of a trackway. More particularly, the invention relates to a truck which is manufactured and sold by National Castings Incorporated of Lisle, Ill. under the trademark SWING MOTION. A detailed description of this quality truck with excellent high speed performance characteristics is found in U.S. Pat. No. 3,670,660. The SWING MOTION truck is manufactured from many different steel parts, such as a bolster and transom which are coupled transversely between a pair of parallel sideframes between which a pair of axles with attached wheels are mounted for rotation. The transom is generally parallel to the bolster, but in closer spaced relation to the trackway, when the truck is mounted on the trackway. The transom has a pair of opposing ends which are mounted on similar rocker seats that are supported on hardened steel, rocker seat bearings which are designed to rest in channel-shaped recesses that are formed in the sideframes below the connection of the bolster ends with the sideframes. Unfortunately, continued wear causes the connection between the transom and rocker seats to loosen which can adversely effect operation of the truck at high speeds. Such wear is accelerated, if the rails of the trackway are wavy or misaligned. The invention is directed to eliminating or substantially reducing this problem by the provision of a more rigid connection between the transom and the rocker seats.
Briefly stated, the invention comprises forming specially shaped holes in the transom ends and rocker seats to receive uniquely contoured nuts and bolts which are designed to hold the rocker seats firmly in compressive engagement with the overlapped ends of the transom, even after extended use of the truck produces excessive wear on the connections between the transom and rocker seats.